Time is running out on these two operating systems from Microsoft. The end of support is slated for later this year on October 10, 2023. If you continue to use either of these operating systems after that date you are putting your business at risk. Security updates are available to those with an extended service contract from Microsoft. Another alternative is to move your server instance to the Azure cloud. If you want to continue using of your on-premise server, upgrading to Windows Server 2022 is recommended. More information from Microsoft is available here.